B6 Performance - Suspension Strut Assembly. Bilstein B6 Performance dampers are a performance upgrade to OE dampers designed to be paired with the OE factory spring. These dampers offer application specific valve settings with a monotube design to bring out the best handling performance of a vehicle. Each damper is rigorously tested for quality that meets or exceeds OE standards. B6 Performance dampers will provide improved safety and handling performance with the added benefit of world-famous Bilstein quality.